What is "Base Address" in Simulink Real-Time RS-232/422/485 Setup block?

Hi all:

I'm trying to read from an IMU through COM port on a PC104, in Simulink Real-Time. Since there's no existing block specified for this PC104, the only applicable blocks are those under Simulink Real-Time/RS232/MainBoard/Baseboard Serial Internal blocks/.

Problem is the setup block there requires a "Base Address" (shown below) which is not clearly explained in its help doc.

My question is: is this "Base Address" the address of the COM port? For example, the COM port on my PC104 has address 3F8-3FF, so I will need to use 3F8 as the "Base Address"?

Another question is about the FIFO mode: the IMU I'm using does not seem to have a FIFO, I did notice that there was a "1 deep" FIFO mode, does it essentially mean "No FIFO"?

Any help would be greatly appreciated. Thanks for your time!

Answer 1

[Brandon Eidson]

Hey Chuanzheng,

The "Base Address" refers to the ISA address of the COM port on your target machine. You have to get it from the bios on your target machine. You are somewhat on the right track in that that address will be between 0x3F8 and 0x3FF.

The "1 deep" setting for "FIFO Mode" just means that it is not using a buffer. You should use this if your device does not have a buffer.

[Walter Roberson]

It might mean that it has a buffer of 1 value, so that it could be receiving the next value while waiting for the just-read value to be retrieve. If there was no buffer at all then as soon as the next value started to arrive, the value that had just been read it would have to be invalidated.

[Pech Viden]

Hey Brandon, My target pc com port address is 0x3F8 and 0x2F8(main board). It seems like when I try to fill it with 3F8 or 0x3F8, it does't work. Pls help me out!!

[Diego Kuratli]

Try hex2dec('3f8')

However, I would use the Baseboard block instead. The Baseboard block is already configured for the COM1/2/3/4 standard port addresses and IRQs. Examples are provided in the Help, Simulink Real-Time, Examples.